The vast majority of contemporary flow hematology analyzers measure the scattered or transmitted signals from cells exposed to optical radiation so as to acquire information on the volume and an internal structure of the cells. Their specific work process can be summarized as follows: An emitting optical system is employed to focus a beam emitted from a light source into a hollow sheath flow chamber, wherein fluid focusing principles are exploited to force cells in sequence through a focal region. Light transmitted or scattered by the cells is collected by a receiving optical system on a photoelectric detector, where the optical signals are further subjected to data processing so as to obtain the desired information on cell volume, internal structure and the like. The structure of a typical hematology analyzer optical system device is shown in FIG. 1. In such a system, the emitting optical system and receiving optical system are typically composed of one or more optical lenses.
When using a hematology analyzer optical system device of the type shown in FIG. 1, during the actual commissioning and production process it is necessary to accurately align the center of the light spots obtained by focusing the emitting optical system with the position of the cells in the sheath flow chamber, i.e., the x, y and z coordinates of the optical system all need to be aligned.
In traditional optical systems, as the optical paths arising from mutual coupling of multiple degrees of freedom make alignment difficult, in actual production it is necessary to employ a dedicated alignment apparatus and commissioning procedure, which lowers production efficiency and increases the cost of production. Not only this, but the emitting and receiving optical systems are also required to possess light source shaping and focusing functions, so that multiple (e.g., four to six) optical transmission lenses are necessary to achieve the desired image quality. Multi-lens optical systems also require precise tuning, and are further hampered by constraints such as complex commissioning and long processing times.